<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <style>
    .box {
      width: 300px;
      height: 200px;
      background: url('https://via.placeholder.com/300x200') no-repeat center/cover;
      border: 2px solid #333;
      color: white;
      text-align: center;
      line-height: 200px;
      font-weight: bold;
    }
  </style>
</head>
<body>
  <div class="box">背景示例</div>
</body>
</html>
